The present invention relates to an apparatus adapted for the recovery of fluid substances floating on water surfaces or other calm liquids.
Various types of devices are already known for the recovery of fluid material which floats on calm water surfaces and which can be called of a "dipping" type, as, for instance, a system including disks or rollers rotating about a horizontal axis, or systems including a belt in continuous motion.
Said devices are caused to be lapped by the surface layer of the liquid so as to gather the oil layer therefrom which remains sticking to a gathering means and from which the oil is removed by the use of scraping means.
Already known are the apparatus which are called the "weir" type, comprising a body substantially of a well-like shape, the edge of which is maintained immersed below the liquid surface at a predetermined level by means of a system of floating bodies supporting the apparatus and through the bottom of which by means of pumps the surface layer of the liquid is removed, which flows over the sill.
However these devices have, in general, a very low efficiency, chiefly owing to the poor draw capacity which can be exterted on the outer liquid layer, while those of the "well" type present also the disadvantage that they remove, together with the polluting layer, a considerable amount of water which later must be separated from the oil at further expense.